Single-injection device

ABSTRACT

A single-injection syringe, including a liquid container to be filled with the medicament, and holding at its sealed lower end a shortened or long syringe body which, in its interior, carries a movable needle support and forms with a piston rod a sterile chamber.

[ Nov. 4, 1975 United States Patent [1 1 De Felice V N 8 l 2 8 2 I M er. h 10. K

[ SINGLE-INJECTION DEVICE [75] Inventor: Wilfried De Felice, Kelkheim,

Taunus, Germany [73] Assignee: Hoechst Aktiengesellschaft,

VDARR 8D88 o en 8288 WZWZZ 1 11 mm m m N udd wmmmm m KKm e dd m d m mwunIIS r a n n u FCUUA 06096 65766 99999 HHHHH 03957 99 26 5722 235 832054 w e G .m m

4 7 m9 n 1 a 6 4 m 2 1 m 0 m x s F M 4 0 N m 0 p F A 1. 1 2 l 2 2 I .1

[30] Foreign Application Priority Data PrimaryExaminerRichard A. GaudetMar. 28, 1973 Assistant 0P1ltz Attorney, Agent, or Firm-Curtis, Morris &Safford ABSTRACT A single-injection syringe, including a liquidcontainer 1. 7 5 r1 mRM Hyoooo 2 ll M22 2 IIDMMN m 28 n 1 WWV MM P mm oomnn2 "m mu A mm HD umuoo n m m m Mm m m 8 l m m Q 1 I 0 Cmu m l m UhF1:1] 2 8 555 to be filled with the medicament, and holding at its 5References Cited sealed lower end a shortened or long syringe bodywhich, in its interior, carries a movable needle support UNITED STATESPATENTS and forms with a piston rod a sterile chamber.

I-Ioskins 2,542,814 2/1951 128/218 D 3,084,688 4/1963 McConnaughey128/218 NV 4 Claims, 4 Drawing Figures n lnrlululnlllllllfil llll 1SINGLE-INJECTION nnvrca The present invention relates to asingle-injection de vice consisting of a liquid container of specialshape to be filled with a liquid medicament. The sealed lower end of thecontainer holds a syringe body which, however, may also cover the liquidcontainer over its full length. The interior of the syringe body isprovided with a movable needle support and forms a sterile chambertogether with a piston rod.

So-called ready-to-use syringes used for a single injection are alreadywidely employed in the medicinal administration technique. Owing to themany individual parts of such wholesale articles, the assembly to bemade under sterile conditions involves considerable cost. Since aready-to-use syringe is destined for one injection only, themanufacturer will strive to keep the production costs thereof as low aspossible.

Prior art knows injection devices, in which the medicament to beinjected is stored in a liquid container, shaped as an ampoule which ispushed into a syringe body. In the final assembly, the ampoule placed inthe syringe body will be pushed in only to such a point that theassembled injection cannula which reaches into the interior of thesyringe body does not pierce the seal at the front end of the ampoule.An essential disadvantage of that syringe is the injection needle fixedin the syringe body, since the needle portion which projects into thesyringe body and the portion of the ampoule facing it have to be keptsterile. Because of the resulting space between the liquid container andthe syringe body, however, micro-organisms can penetrate into thesterile zone within a certain length of time in storage.

The present invention makesit a point to provide a sterile zone for theinjection needle not in the syringe body but in a sealed and separatepart of the device. This is achieved by mechanically deforming thesyringe body proper into engagement with the liquid container, thusproviding a sealed sterile chamber.

The syringe, constructed in accordacne with the present invention, willnow be described in greater detail by way of example only with referenceto the accompanying drawings, in which:

FIG. 1 is a side view of the syringe;

FIG. 2 is a longitudinal cross sectional view of the sy ringe with thesyringe body shortened;

FIG. 3 is a longitudinal cross sectional view of the syringe with thesyringe body covering the liquid container;

FIG. 3a is a top view of the upper end of the syringe as shown in FIG.3.

Referring to the drawings, FIG. 2, A and FIG. 3, B show the syringe bodyin its shortened form and in its long form respectively, the fingersupport 5 in the first case being part of the liquid container, whereasin the second case it is part of the syringe body.

If the liquid container to be filled with the medicament has such ashape that no means is provided for a firm connection with the syringebody, the preferred method for securely fastening the containeraccording to the invention is provided by thermically and megchanicallydeforming a projecting portion of the rim 4 (FIG. 3) of the syring bodymade of a suitable plastic material by means of a punch moved in thedirection of the container axis so as to form beads (FIGS. 3 and 3a) toretain the container. These retaining beads Qprevent the liquidcontainer from being removed, while compensating for differences in thetotal length of the liquid container, as do also various securing meansof injection devices as presently used, for example stoppets withannular sealing lamellae or threads or socalled bayonet-type sealings.

To overcome the above-mentioned disadvantages l have now developed a newsyringe system comprising essentially the following three main parts, asshown in FIG. 1: A container 1 to be filled with a liquid medicament, ashortened and/or a long syringe body 2 and a piston rod 3 mounted on thesyringe body.

Referring to FIGS. 2 and 3, the liquid container is sealed in a familiarmanner at its rear end by means of a movable piston stopper 6 and at itslower end by means of an aluminium cap 7 having a central aperture,under which a rubber disk or a rubber stopper 8 is inserted. The sealingplug of the rubber stopper is advantageously provided with a conicalcavity, through which air bubbles, which frequently form in the interiorof the container filled with the liquid medicament prior to theapplication, can simply be removed by pressing the piston rod.

The liquid container 1 may be separated from a bore 9 holding the needlesupport 10, with a cannula ll passing through, by means of a plasticmembrane 12, which may be injection-molded onto the syringe body 2,which is made of a plastic material. Moreover, the surface of the needlesupport 10 is provided with an annular projection 13 which engages anannular groove 14 cut in the bore 9, thus securing the needle support 10in its initial position. This prevents premature perforation of themembrane 12 and the piercing of the rubber disk or stopper 8 placedunder the aluminium cap 7. Four stabilizing fins 15, runningperpendicular to the plane of the annular projection 13 on the needlesupport 10, assure pefect centering in the bore 9.

The lower end of the needle support 10 is frustroconical, preferablyshaped as a record frustrum l6, and has a shoulder 17, so that a plasticsocket 18 projecting in the interior of the piston rod 3 can engage theneedle support 10. In the case of a long cannula which,

as the same time, is the injection needle, a frustrum 18 is notrequired.

The syringe body 2 with the piston rod 3 screwed on and the needlesupport 10 located inside it may be sterilized in ways already known,for example by using gamma rays. The device is secured againstinadvertent twisting of the piston rod 3 by spot welding, which alsopresents the advantage of tamper-proof sealing.

In order to operate the syringe of the invention, the piston rod 3 isturned until retained by a stop 21. The

projecting end of the cannula 11 thereby pierces the plastic membrane 12and the rubber sealing 8, thus establishing a communication to theinjection solution. The piston rod 3 is then removed by simple reversedturning and screwed into the piston stopper 6 placed at the upper end ofthe medicament container 1.

The injection needle, the size of which depends on the intendedinjection, is then placed on the record frustrum 16 of the needlesupport 10. It is also possible to use the injection cannula 11, whichprojects beyond the frustrum and is firmly connected to the needlesupport 10, as an injection needle. The injection device of of theinvention has the advantage that the whole can'- nula is located in asterile chamber, that fractionation of the rubber disk or stopper andthus clogging of the cannula are avoided to a large extent and that, inthe case of a long syringe body, provision of retaining beads ensures alocking effect which is superior to conventional types and, inter alia,ensures perfect aspira tion. The retaining beads provide a reliablemeans of preventing the liquid container from falling out of the syringeor being exchanged unintentionally.

I claim:

1. A single-injection syringe, comprising a container for a medicament;said container having first and second open end positions; said firstend portion of the container having a penetrable seal mounted thereinfor sealing said first end portion, and said second end portion having apiston inserted therein to define with said seal a chamber forcontaining the medicament; a sy ringe body mounted on and surroundingsaid first end portion of the container; said syringe body having apenetrable end wall extending across said first end portion of thecontainer and an elongated generally cylindrical sleeve integrallyformed with and extending from said wall; said sleeve having anelongated bore formed therein extending from said end wall to an openend located in spaced relation from said end wall and a threadedexternal periphery; a needle support mounted in said bore for movementbetween first and second positions therein; said needle support having adiameter which is slightly less than the diameter of said bore andincluding an annular projection formed thereon and at least fourstabilizing fins extending perpendicularly thereto into engagement withthe bore; a needle mounted in said support having an end portion locatedwithin said bore in the first position of the needle support andpiercing said end wall and said seal as it is moved to its secondposition; said bore of said sleeve having a pair of spaced annulargrooves formed therein respectively defining the first and secondpositions of said needle, said groove receiving and cooperating withsaid annular projection on the needle support to hold the needle supportin its respective positions against inadvertent movement in the sleeve;and a hollow plunger including a first end portion threadably engagedwith said threaded sleeve and operatively engaged in bearing engagementwith said support, and a second end portion having means formed on theexterior thereof for engaging said piston when the plunger is removedfrom the sleeve; said needle support also including an annular shoulderformed thereon; and said plunger having an annular socket formed thereinat its first end portion operatively engaging said annular shoulder inbearing engagement to urge said support towards the syringe body tocause the needle to pierce the end wall and seal upon rotation of theplunger on the sleeve when the plunger is rotated on the sleeve in adirection to move it towards the syringe body, said plunger having anelongated chamber formed therein receiving said needle, whereby saidneedle support forms, with the end wall of said syringe body an enclosedsterile chamber for the needle and is moved from its first to its secondposition to cause said needle to pierce said end wall and said seal whensaid plunger is threaded on the sleeve in a direction to move it towardsthe syringe body.

2. A syringe as claimed in claim 1 wherein said seal is a rubber stopperand has a conical cavity formed therein opening towards said chamber atthe position at which the needle will pierce the'seal.

3. A syringe as claimed in claim 1 wherein said syringe body extendsonly about said first end portion of the container and the liquidcontainer has a flanged-out finger support formed thereon.

4. A syringe as claimed in claim 1 wherein the syringe body surroundsthe entire container and has, adjacent the second end portion of thecontainer, radially inwardly extending beads overlying the container forretaining the liquid container in the syringe body.

1. A single-injection syringe, comprising a container for a medicament;said container having first and second open end positions; said firstend portion of the container having a penetrable seal mounted thereinfor sealing said first end portion, and said second end portion having apiston inserted therein to define with said seal a chamber forcontaining the medicament; a syringe body mounted on and surroundingsaid first end portion of the container; said syringe body having apenetrable end wall extending across said first end portion of thecontainer and an elongated generally cylindrical sleeve integrallyformed with and extending from said wall; said sleeve having anelongated bore formed therein extending from said end wall to an openend located in spaced relation from said end wall and a threadedexternal periphery; a needle support mounted in said bore for movementbetween first and second positions therein; said needle support having adiameter which is slightly less than the diameter of said bore andincluding an annular projection formed thereon and at least fourstabilizing fins extending perpendicularly thereto into engagement withthe bore; a needle mounted in said support having an end portion locatedwithin said bore in the first position of the needle support andpiercing said end wall and said seal as it is moved to its secondposition; said bore of said sleeve having a pair of spaced annulargrooves formed therein respectively defining the first and secondpositions of said needle, said groove receiving and cooperating withsaid annular projection on the needle support to hold the needle supportin its respective positions against inadvertent movement in the sleeve;and a hollow plunger including a first end portion threadably engagedwith said threaded sleeve and operatively engaged in bearing engagementwith said support, and a second end portion having means formed on theexterior thereof for engaging said piston when the plunger is removedfrom the sleeve; said needle support also including an annular shoulderformed thereon; and said plunger having an annular socket formed thereinat its first end portion operatively engaging said annular shoulder inbearing engagement to urge said support towards the syringe body tocause the needle to pierce the end wall and seal upon rotation of theplunger on the sleeve when the plunger is rotated on the sleeve in adirection to move it towards the syringe body, said plunger having anelongated chamber formed therein receiving said needle, whereby saidneedle support forms, with the end wall of said syringe body an enclosedsterile chamber for the needle and is moved from its first to its secondposition to cause said needle to pierce said end wall and said seal whensaid plunger is threaded on the sleeve in a direction to move it towardsthe syringe body.
 2. A syringe as claimed in claim 1 wherein said sealis a rubber stopper and has a conical cavity formed therein openingtowards said chamber at the position at which the needle will pierce theseal.
 3. A syringe as claimed in claim 1 wherein said syringe bodyextends only about said first end portion of the container and theliquid container has a flanged-out finger support formed thereon.
 4. Asyringe as claimed in claim 1 wherein the syringe body surrounds theentire container and has, adjacent the second end portion of thecontainer, radially inwardly extending beads overlying the container forretaining the liquid container in the syringe body.